Chemistry and Phystes. 237 
inside the experimental space. The experimental vessel consisted 
ver was surrounded by water which was 
i atap. The radiating surface at the mouth of 
the bell jar was heated by a jet of steam, and the details of the 
as to avoid the production of 
to aqueous va- 
eneral discussion of the meteorological bearing of 
amount of 
absorption is known for the different parts of the spectrum.— 
. der K. Akad. der Wissensch. in Wien, July, 1880; Phil. 
81 Pa 
SR eee es 
8. Dust, Frogs, and Clouds.—Mr. Joun AITKEN, in a pa 
Sented to the i 
that dust is essential for the formation of fogs and clouds. Steam 
was mixed with air in two arge glass receivers; one of these 
;celvers was filled with common air, the other with air which 
sé 
s 
Cy 
5 
ay 
CO 
